Process for producing ternary thio compounds



Sept. 15, 1964 A. CLEARFIELD 3,148,998

PROCESS FOR PRODUCING TERNARY THIO COMPOUNDS Filed Feb. 2, 1960 INVENTORABBAIMM CLEARFIELD BY M ATTORNEY United States Patent 3,1433% PRQCESSFER PRGDUCHNG TEPNARY Tint) COMPOUNDS Abraham Clearfield, Niagara Falls,NXZ, assignor to National Lead Company, New York, N.Y., a corporation ofNew .lersey Fiied Feb. 2, 1960, Ser. No. 6,269 7 Ciairns. (Cl. 196-299)This invention relates to ternary sulfides of alkali metals and alkalineearth metals with titanium and zirconium. It is particularly concernedwith a novel process for producing such compounds and with certain novelthiozir conates and thiotitanates.

It has previously been known that thiotitanates of alka line earthmetals can be prepared by heating together a mixture of an alkalineearth metal sulfide and titanium sulfide. The reaction involvedpresumably is represented by:

However, since the separate preparation of titanium disulfide isnecessary in this method, an easier way of producing these compounds hasbeen considered desirable. It has also been desired to produce otherdouble sulfides of titanium as well as those of zirconium.

An object of the present invention is, therefore, to provide a practicaland convenient process for the preparation of alkali metal and alkalineearth metal thiozirconates and thiotitanates.

Another object of the present invention is to provide a process for thepreparation of alkali metal and alkaline earth metal thiozirconates andthiotitanates which utilizes only easily obtained reacting materials.

A further object of the invention is to provide novel ternary sulfidesof alkali metals and alkaline earth metals with titanium and zirconium.

Other objects and advantages of the present invention will be apparentfrom the following description of the nature and practice of theinvention taken in conjunction with the accompanying drawing whichillustrates diagrammatically apparatus by which the novel process may becarried on.

The preparation of thiozirconates and thiotitanates (which terms aremeant to designate ternary compounds, in which sulfur has replaced theoxygen of metallic zirconates or titanates, with typical formulas suchas BaZrS and BaTiS according to the present invention involves theheating of alkali metal or alkaline earth metal zirconates or titanates,as the case may be, in an atmosphere of carbon disulfide and in theabsence of air, This is preferably done in apparatus like thatschematically illustrated in the accompanying drawing. In this, thenumeral 11 indicates an electrically heated fur nace of the Lindbergtype provided with electrical leads 12 and a heating chamber 13 fromwhich air may be excluded. An inlet line 14 is provided to supply dryargon and carbon disulfide vapor to the chamber 13 and an exhaust line15 is provided to lead waste gases to suitable apparatus where thesulfur-containing gases may be removed. A pyrometer 16 with leads 17 isprovided in the chamber 13 for determining the temperature therein.

In the following two examples there is described, re-

spectively, the preparation of barium thiozirconate and 3,1483% PatentedSept. 15, 1964 barium thiotitanate according to the present novelprocess.

EXAMPLE 1 A quantity of barium zirconate (BaZrO is placed in a zirconboat 18 in the heating chamber 13 of the furnace 11. The chamber 13 thenis evacuated by connection of a vacuum pump (not shown) to the exhaustline line 15 therefrom. After evacuation the chamber is filled withargon through the line 14. The temperature in the chamber is then raisedto 1050 C. and argon carrying the CS vapor is passed through the chamberfor 4 hours. The product in the boat is found to be a bluishblack,granular material of approximately 4.8 specific gravity, analyzing Ba42.3%, Zr 28.1%, S 28.6%. The analytical results are within normalexperimental error of the theoretical composition: Ba 42.16%; Zr 28.31%,S 29.53% for barium thiozirconate (BaZrS It is also found that the X-raydiffraction pattern of the product is distinct and unlike that of bariumzirconate, barium sul fide, or zirconium sulfide. It does, however,correspond to the X-ray diffraction pattern of barium thiozirconateproduced by heating together barium sulfide and zirconium disulfide.

EXAMPLE 2 Using procedures similar to that employed in Example 1, bariumtitanate (BaTiO is heated for 4 hours at 1000 C. in an argon and carbondisulfide atmosphere to obtain a black, crystalline product whichanalyzed Ba 47.8%, Ti 17.2%, S- 33.5%. This corresponds to thetheoretical composition for barium thiotitanate (BaTiS which is Ba48.80%, Ti 17.02%, S 34.18%. The product has the same X-ray ditfractionpattern-as that found for barium thiotitanate'prepared by the knownmethod previously mentioned.

The preparation, according to the present invention, of lithiumthiozirconate and lithium thiotitanate, is described in the followingtwo examples. These examples typify the production of alkali metal thiocompounds with titanium and zirconium.

EXAMPLE 3 Lithium thiozirconate is made by procedure like that describedin Example 1, using as a starting material lithium zirconate (Li ZrO andheating it in argon and carbon disulfide vapor for 16 hours at 1050 C.The novel product is a granular crystalline material, deep violet incolor. It has an X-ray diffraction pattern with strong peaks at 6.11 A.,2.62 A., and 1.85 A. that appears to be unique and is distinct from thepatterns of lithium zirconate, lithium sulfide and zirconium sulfide.Analysis of the product shows Li 6.09%, Zr 45.4%, S 45.31%. This is veryclose to the theoretical composition of Li 6.86%, Zr 45.59%, S 47.55%.

EXAMPLE 4 Using the same procedure described in Example 1, lithiumtitanate (Li TiO is heated for 20 hours at 900 C. in an atmosphere ofcarbon disulfide vapor and argon to obtain lithium thiotitanate. This isa granular, crystalline, brownish-black material. It is also found tohave a distinctive X-ray diffraction-pattern characterized by peakswhich are not found in the patterns of the individual sultides or theoriginal lithium titanate.

Other novel alkali metal and alkaline earth metal thio- =3 zirconatesand thiotitanates are produced by employing the same procedure as thatdescribed above in Example l. The following examples give detailsconcerning the production of these products.

EXAMPLE 5 Potassium thiozirconate (K ZrS is prepared from potassiumzirconate (K ZrO by reaction with CS in argon at 1000 C. for 24 hours.It is a well crystallized, granular material with a purple or violetcolor and a hitherto undescribed X-ray diffraction pattern which,however, resembles that of lithium thiozirconate.

EXAMPLE 6 Potassium thiotitanate (K TiS is prepared from potassiumtitanate (K TiO by reaction with CS at 900 C. for 24 hours. Thegranular, crystalline product is brownish-black in color. Like the otherthiotitanates and thiozirconates this product has a distinctive andapparently unique X-ray ditiraction pattern. The X-ray pattern is verysimilar, however, to that of lithium thiotitanate.

EXAMPLE 7 Sodium thiozirconate (Na ZrS is produced by the reaction ofsodium zirconate (Na ZrO with CS in argon at 1000 C. for 17 hours. Thegranular crystalline product is black and has an apparently unique X-raydifiraction pattern which, however, is quite similar to that of lithiumthiozirconate.

EXAMPLE 8 By reacting sodium titanate (Na TiO with CS in argon at 1000"C. for 24 hours sodium thiotitanate (Na TiS is produced. This is ablack, crystalline material which has a distinct X-ray diffractionpattern which is not characteristic of sodium titanatc, sodium sulfideor titanium sulfide but closely resembles the X-ray patterns ofpotassium and lithium thiotitanates.

EXAMPLE 9 4 Calcium thiozirconate (CaZrS is obtained by reacting, at1000 C. for 24 hours, calcium zirconate (CaZrO with CS in an argonatmosphere. The granular, crystalline product is black and has adistinct and previously unknown ditfraction pattern. Analysis showed itto have the composition: Ca 17.7%, Zr 39.5%, S 42.0%. This correspondsclosely to the theoretical composition: Ca 17.54%, Zr 40.37%, S 42.09%.

EXAMPLE l0 Strontium thiozirconate (SrZrS is produced by the reaction ofstrontium Zirconate (SrZrO with CS in argon at 1000 C. for 20 hours. TheX-ray diffraction pattern of the black crystalline product shows it tobe novel and isomorphous with calcium tbiozirconate.

It has also been possible to produce, by the present novel method,calcium thiotitanatc (CaTiS and strontium thiotitanate (SI-T183) both ofwhich have been previously prepared by another procedure. Temper-aturesof 900 C.l 100 C. are employed with heating times of from 6 to 24 hours.

In Examples 1 and 2 the production of barium thiozirconate and bariumthiotitanate is described. It has been found that by varying thetemperature of reaction in the described method novel colored productsof varying composition can be obtained. This is illustrated in thefollowing examples.

EXAMPLE 1 1 Using apparatus like that shown in the drawing and thegeneral procedure described in Example 1 barium zirzconate is heated inan atmosphere of argon and carbon disulfide for 4 hours at atemperataure of 800 C. There is obtained a dark maroon, crystallinepowder containing 15.3% sulfur. X-ray examination indicates that 2+ theproduct consists of approximately 45% BaZrO 40% BaZrS and 15% of anunidentified third phase.

By varying the temperature of reaction, powders having a wide range ofcolor and sulfur content and varying degrees of crystallinity areobtainable, as set forth in the following table. In each case theheating time was 4 hours and the composition was estimated from X-raydata.

Table A Product Reaction Temperature,

Degrees C Perient Color Estimated Composition Yeliowish BEZIOs.Yell0w-orange BaZrOs. Deep orange BaZrOs 4.18 Orange-red Bzigroi 88%,BaZrSa 9.65 Rust BaZrOa 65%, BaZrS;

25%, X 10%. 900 21.2 Violet BaZrOa 20%, BaZrS 65%, X 15%. 27.1 GreyblackBElZISs. 28.6 Blue-black BaZrS Table B Reaction Time, Hours ProductReaction Temperature, Degrees C.

Color Percent S 4 Rust 6 Deep red 12 Maroon 18 Violet 20 (approx).

Products having different colors can also be obtained by varying thereaction conditions during the heating of barium titanate in anargon-carbon disulfide atmosphere. At temperatures of 700 C.l000 C. aheating time of 4 hours results in the production of a black,crystalline barium thiotitanate. However, if a temperature of 400 C. isemployed the product is pale violet in color and the composition asdetermined by X-ray is still BaTiO At a temperature of 500 C. the colorof the granular product is a deeper violet and the composition is foundto be BaTiO -5% BaTiS Carrying out the reaction for 4 hours at 600 C.results in a violet-black crystalline composition which is shown byX-ray diffraction to be 70% BaTiO -30% BaTiS It is to be noted that thecolored products obtained by heating barium titanate and bariumzirconate in carbon disulfide vapor are produced only by the methoddescribed. Attempts made to produce them by heating mixtures of bariumsulfide with titanium disulfide and with zirconium disulfide have beenunsuccessful. I

In carrying out the process of the present invention to producethiotitanates and thiozirconates of the alkali and alkaline earth metalsone may start, as in the preceding examples, with a titanate orzirconate of the desired metal. If desired, however, one may use as astarting material a compound, such as barium titanium oxalate, whichdecomposes to form barium titanate on heating to 1000 C. It is alsopossible to use other oxygen-containing compounds such as mixtures ofoxides or hydrous oxides or compounds such as carbonates, etc. which atthe temperatures involved in the process decompose to oxides or reactlike oxides to form zirconates or titanates. The term oxide as employedin the claims 5 includes such compounds. The following examplesillustrate such variations.

EXAMPLE 12 Using apparatus like that illustrated in the drawing and theprocedure described in Example 1 finely divided barium titanium oxalateis heated for 4 hours at a temperature of 1000 C. in an atmosphere ofargon and CS vapor. A black, crystalline, granular product is obtainedthat by X-ray difiraction appears to be identical with the bariumthiotitanate product of Example 2.

EXAMPLE 13 If an intimate mixture of finely divided lithium carbonateand ZrO in equi-molar amounts is heated for 20 hours at 1056 C. in anatmosphere of argon and carbon disulfide vapor there is produced ablack, crystalline product. This is found by X-ray dhfraction to be thesame as the lithium thiozirconate of Example 3.

As shown by the following example, the materials employed may be, ifdesired, more or less impure commercially available products.

EXAMPLE 14 EXAMPLE 15 A brushing lacquer is produced by compounding thefollowing:

Parts by weight Cellulose acetate-butyrate ester 18 Acetone 20 Butylacetate 25 Ethyl lactate l0 Ethyl alcohol 22 Tricresyl phosphate Thecellulose ester is dissolved in the acetone and butyl acetate and theviscous mixture is thinned by add ing the ethyl lactate, alcohol, andtricresyl phosphate plasticizer. There is then dispersed in the vehicle30 parts by Weight of very finely ground lithium thiozir conate. Thisresults in a lacquer which when brushed on metal tile and dried gives avery pleasing violetcolored coating.

Coatings of other colors can be obtained by substituting for the lithiumthiozirconate in the lacquer above described other ternary sulfides ofthe group disclosed herein or the variously colored products resultingfrom the heating of barium titanate and barium zirconate with CS underdifierent conditions. A variety of attractive appearing coatings canthus be produced. Other vehicle compositions may, of course, be employedand, if desired, mixtures of the colored pigments with each other and/or with other suitable pigments may be used. Since the 6 pigments of thepresent invention contain sulfur, it will, of course, be recognized thatlead pigments, for example, are not suitable ones for such mixtures.

It will be understood that in carrying out the process of the presentinvention other suitable apparatus may be used. Further, other inertgases may be used instead of argon with equally good results.

I claim:

1. A process for producing ternary sulfides which comprises heating at atemperature of from about 400 C. to about 1100 C. and for a period of atleast about 4 hours in the presence of carbon disulfide vapor and in theabsence of air, a charge comprising an oxide of a metal selected fromthe group consisting of zirconium and titanium and an oxide of a metalselected from the group consisting of alkali metals and alkaline earthmetals.

2. A process as set forth in claim 1 in which said charge comprises anoxygen-containing compound of a metal selected from the group consistingof zirconium and titanium and a metal selected from the group consistingof alkali metals and alkaline earth metals said compound at thetemperatures involved in the process decomposing to form a compound ofthe group consisting of zirconates and titanates of alkali and alkalineearth metals.

3. A prowess for producing ternary sulfides of alkali metals andalkaline earth metals with zirconium and titanium which comprisesheating at a temperature of from about 400 C. to about 1100 C. and 'fora period of at least about 4 hours in the presence of carbon disulfide'vapor and in the absence of air a compound selected from the groupconsisting of zirconates and titanates of alkali metals and alkalineearth metals.

4. A process as set forth in claim 3 in which said alkali metals andalkaline earth metals are selected from the group consisting of Na, K,Li, Ba, Sr, and Ca.

5. Colored compositions resulting from the heating to partially but notcompletely replace the oxygen thereof with sulfur of a compound of thegroup consisting of BaTiO and BaZrO in an atmosphere of carbon disulfidevapor and in the absence of air at temperatures of from 400 C. to 11G0C., said compositions being Variable in composition but containingsulfur and being composed in at least major part of at least onecompound selected from the group consisting of BaTiO and BaTiS in thecase of those compositions derived from BaTiO and being composed atleast in major part of at least one compound selected from the groupconsisting of BaZrO and BaZrS in the case of those compositions derivedfrom BaZrO and the color of said compositions and the sulfur contentthereof being variable with the time and temperature of heating.

6. A colored composition as set forth in claim 5 in which BaTiO isheated.

7. A colored composition as set forth in claim 5 in which BaZrO isheated.

OTHER REFERENCES Hahn et al.: Zeitschrift fur Anoranische and AllgemeineChemie, vol. 288, pages 269-278 (1956).

5. COLORED COMPOSITIONS RESULTING FROM THE HEATING TO PARTIALLY BUT NOTCOMPLETELY REPLACE THE OXYGEN THEREOF WITH SULFUR OF A COMPOUND OF THEGROUP CONSISTING OF BATIO3 AND BAZRO3 IN AN ATMOSPHERE OF CARBONDISULFIDE VAPOR AND IN THE ABSENCE OF AIR AT TEMPERATURES OF FROM 400*C.TO 1100*C., SAID COMPOSITIONS BEING VARIABLE IN COMPOSITION BUTCONTAINING SULFUR AND BEING COMPOSED IN AT LEAST MAJOR PART OF AT LEASTONE COMPOUND SELECTED FROM THE GROUP CONSISTING OF BATIO3 AND BATIS2 INTHE CASE OF THOSE COMPOSITIONS DERIVED FROM BATIO3 AND BEING COMPOSED ATLEAST IN MAJOR PART OF AT LEAST ONE COMPOUND SELECTED FROM THE GROUPCONSISTING OF BAZRO3 AND BAZRS3 IN THE CASE OF THOSE COMPOSITIONSDERIVED FROM BAZRO3 AND THE COLOR OF SAID COMPOSITIONS AND THE SULFURCONTENT THEREOF BEING VARIABLE WITH THE TIME AND TEMPERATURE OF HEATING.